Mouthguards are used in a variety of environments to prevent or reduce injuries to the inside of the mouth, teeth, and the jaw by absorbing some or all of the impact of blows to the face and head. The use of mouthguards is especially well known in such sports as football, hockey, boxing and other contact sports in which blows to the face and head are expected. Within the past few years, the use of mouthguards has extended to other sports such as basketball in which accidental blows can occur. Mouthguards can prevent concussions, tissue damage to the mouth, loosening of teeth, and misalignment and dislocations of the temporal-mandibular joint.
Two main factors are important in fabricating a mouthguard. First, the mouthguard must be able to absorb the shock of blows to the head, face, and teeth to prevent the injuries described above. Second, the mouthguard must be comfortable in the user's mouth. These two factors can often be conflicting as harder more rigid materials may absorb blows more effectively but are more uncomfortable when worn as they do not easily conform to the contours of the mouth. Conversely, a softer mouthguard may be more comfortable but less able to absorb blows sufficiently to prevent injuries. In addition, it is important to shape the mouthguard to allow the user to breath easily and without obstruction when playing a particular sport and to enable a user to easily keep the mouthguard in his or her mouth.
Kittelsen, et al. are inventors of a family of patents disclosing a mouthguard in which a nonsoftenable frame is covered by a skin of softenable substance. U.S. Pat. Nos. 6,588,430, 6,691,710, and 6,675,807 all disclose a mouthguard that also includes a detached lower part with projections that fit into aligned holes in the upper portion. The mouthguard is formed by placing it in boiling water to soften and then biting down on the guard. One drawback is that the softenable material is only a skin and thus may not be thick enough to both provide protection from impact and still be comfortable to wear.
Therefore, there remains in the field a need for a mouthguard fabricated from thermoplastic materials that can be softened and molded by the user of the mouthguard.